酸性耕作土壤中Zn、Cd、Cu、Co、Ni和Pb的形态

The fractionation of Zn,Cd,Cu,Co,Ni and Pb in some acid cultivated soils in Fujian

采用连续提取法研究了福建省酸性耕作土壤中Zn、Cd、Cu、Co、Ni和Pb的形态分布及其影响因素.结果表明,各元素水溶态和交换态所占比例均很小,Zn、Co、Ni和Pb均以残渣态和铁锰氧化物结合态为主,Cu以残渣态和有机结合态为主,Cd以碳酸盐结合态与专性吸附态、铁锰氧化物结合态和交换态为主.相关分析表明,土壤理化性质对重金属形态有较大影响,但影响程度因元素而异.Zn、Ni和Co的形态受游离氧化铁、阳离子交换量和粘粒含量的影响较大;Cd和Pb的形态受土壤pH、游离氧化铁和粘粒含量的影响较大;Cu的形态与土壤粘粒含量呈较显著相关.

The fractions of Zn,Cd,Cu,Co,Ni and Pb in some acid cultivated soils in Fujian Province,China were extracted by a sequential extraction procedure and the factors influencing the fractionation were discussed.The results showed that the proportions of water-soluble and exchangeable fractions to the total contents of the metals were quite small.Zn,Co,Ni and Pb were dominated by residual and Fe-Mn oxide-bound fractions;Cu was dominated by residual and organic-bound fractions,whereas Cd was dominated by exchangeable,carbonate-bound and specific adsorbed,and Fe-Mn oxide-bound fractions.The soil properties had important effects on the fractionation of the metals although the effects differed with elements.The fractionation of Zn,Co and Ni was mainly influenced by the contents of free iron and clay,and cation-exchange capacity while that of Cd and Pb by soil pH,and the contents of free iron and clay.The fractionation of Cu only had close correlation with clay content.